Apparatus for supporting and movably guiding oxygen lances for rotating barrel converters in production of steel



Aug. 17, 1965 H. KRAMER 3,201,107

APPARATUS FOR SUPPORTING AND MOVABLY GUIDING OXYGEN LANCES FOR ROTATING BARREL CONVERTERS IN PRODUCTION OF STEEL Filed May 15, 1962 2 Sheets-Sheet 1 IN VE N TOR 1 /501417 KKAMEE H. KRAMER Aug. 17, 1965 GEN APPARATUS FOR SUPPORTING AND MOVABLY GUIDING OXY LANGES FOR ROTATING BARREL CONVERTERS IN PRODUCTION OF STEEL Filed May 15, 1962 2 Sheets-Sheet 2 Arr United States Patent O APPARATUS FUR SUPPORTING AND MOVABLY GUIDING OXYGEN LANCES FOR ROTATHJG CGNVERTERS IN PRODUCTION OF Helmut Kramer, ologne, Germany, assignor to Pintsch Bamag Aktiengesellschaft, Cologne-Bayenthal, Germany, a corporation of Germany Filed May 15, 1962, Ser. No. 194,824) Claims priority, application Germany, May 18, 1961, P 27,171 22 Claims. (Cl. 266-36) This invention relates to oxygen lances in the production of steel, and more particularly to apparatus for supporting and movably guiding such oxygen lances in a swinging and reciprocating cycle during the steel, blowing operation.

In the oxygen steel refining process, which is also sometimes referred to as the Kaldo Process, carried out in inclined, revolving rotary barrel converters, there are used, for the blowing operation, oxygen lances which are introduced through the waste-gas hood into the blowout opening of the rotating converter vessel in such a manner that the ox gen jet strikes the surface of the molten bath at an acute angle.

A During the relatively rapid rotation of the converter vessel, the molten bath is circulated by the rolling action, whereby several main and secondary currents are formed, which collide with each other within the bath and become turbulent. In this manner, new liquid of the bath is continuously brought into contact with the oxygen obliquely inclined revolving rotary barrel converters is that even with the optimum setting of the oxygen jet, the lining of the converter becomes eroded and worn nonuniformly, so that the converter vessel often must prematurely be taken out of operation because a single zone of its refractory lining has become so greatly worn away that there exists the danger of a breakthrough through the wall of the vessel, while at other areas large, portions of the lining still remain in satisfactory condition. Such premature shut-downs are, of course, costly and uneconomical, particularly since before the converter can be again relined, it is necessary to laboriously remove the remaining portions of the old lining.

This non-uniform wear of the lining is caused by the following conditions. Not only does the static pressure of the bath have an influence on the wear and tear of the lining, but also the thermal load thereof. During the process, in the upper surface current of the, molten bath, as well as in the portion of the bath on which the oxygen jet had shortly before been directed, there are released certain violent and intensive chemical reactions, which very rapidly reach the wall of the vessel. Because the distance to the wall of the vessel is short and no sufficient mixing or vortex could have yet taken place, the lining within the reaction range of the oxygen jet is particularly strongly stressed thermally. This creates in the walls of the vessel circular zones of high wear and tear or erosion, which forces a premature shut down and interruption of production.

It is an object of the present invention to provide means for overcoming the above difiiculties in a simple, reliable and effective manner.

It is another object of the invention to provide a device for supporting and movably guiding the oxygen lance on a waste-gas hood so as to attain uniform wear on the refractory walls in a revolving barrel converter.

A further object of the invention is to provide means for supporting and driving an oxygen lance directed against a molten bath so that movement of the oxygen jet from the lance may be adjusted to move at a greater velocity over surface of the bath closer to the converter opening, as compared to the more remote surface areas.

To these ends, and in accordance with the present invention, the lance is held by a guiding member supported in front of the converter blow opening on the waste-gas hood. ,This guiding member i pivotable around a horizontal axis and is connected to an oscillating drive mechanism which is so constructed that it imparts to the guiding member a greater angular velocity over the portion of the guide members travel range which determines the lance movement above the front area of the bath surface, as compared to the other half of its travel range.

It is preferable that the guiding member be swivelingly mounted at its lower end, that is directly on the waste-gas hood, so that a greater angular velocity is imparted to the guiding member from the middle position of its swiveling movement in the upwardly situated range than in the lower half of its swiveling range. As the swiveling propulsion drive, a suitably shaped cam disc may be provided, for example.

By means of the lance support and guide means in accordance with the present invention an exceptionally uniform thermal load is attained on the walls of the vessel. Due to the fact that the angular velocity of the lance movement is greater in the area where the oxygen jet impinges on the bathsurface at a point relatively close to the pivot center of the guiding member, and the fact that the angular velocity becomes smaller the more the point of impact on the bath is removed from the pivot center, the result is achieved wherein the oxygen jet,

when striking the bath surface, acts approximately the same on thevarious zones of the bath.

In addition to this effect, by further increasing the angular swiveling velocity of the oxygenlance in the area of jet impact near to the pivot center of the lance, and by reducing the angular velocity of the lances swiveling movement inremote impact areas of the oxygen jet, there can be created an equalization or compensation such that the oxygen jet in the forward portion of the bath will have to traverse only a short distance to the bath surface and will therefore still be dense and closely concentrated and hardly mixed with waste-gas. Consequently it will impinge with a greater velocity and, therefore, will cause a greater local heating than the less concentrated jet impinging on the rear portion of the bath.

As swing propulsion means for the lance support and guide according to the present invention, particularly suitable is a propulsion mechanism consisting of a crank disc and a coupling member or connecting rod in which the ratio of the length of the coupling member to the radius of the crank is relatively small. Such a propulsion mechanism can be easily adjusted to suit any requirements. By means of a movable mounting of the coupling member on the crank disc, the radius of the crank can be changed so that both the non-uniformity of the swinging movement and the swinging throw or arc can be adjusted.

According to a further modification of the invention, the lance is equipped with rails to moveably guide it axially through a guiding cage constructed as a guiding memberand provided with wheel track rollers, and a forward driving mechanism is arranged between the head of the lance and the guiding cage to axially reciprocate the lance.

By means of this further development of the invention the result is attained wherein the oxygen jet can be directed more intensely onto the bath and can be made to impinge on the more remote areas of the bath surface in a more concentrated form than heretofore, so that the nonuniformity of the swinging movement does not have to be too great to achieve the desired compensating effect. In addition, the device also overcomes a disadvantage of the known oxygen lances and their supports which occurs especially in larger converter vessels.

In special cases, for example after a large addition of scrap, the penetration force of the oxygen jet against the waste-gas atmosphere coming in the opposite direction or its density and radius of influence for the more remote parts of the vessel may be insuificient. Heretofore, this condition could be compensated for only by an increase of the oxygen pressure at the lance entrance. For this reason, the overall oxygen installation had to be designed for operating at relatively high peak pressures. This meant that an oxygen arrangement had to be installed which, on the one hand, was unnecessarily powerful for normal operation and, on the other hand, could not be operated during normal operation with the most advantageous degree of effectiveness.

More rapid melting down of larger masses of scrap, which are mostly located in the rear part of the vessel, is necesary for the reason that large quantities of coarsepiece bodies, as for example remainders of skull-cake or ingot ends, are obstructive in the bath during the vessel rotation and can be dangerous for the walls.

By moving the oxygen lance and directing the lance onto the rearward portion of the bath, the larger pieces situated in the rear of the bath can be quickly melted down without increasing the oxygen pressure.

By means of control devices for the lance reciprocating or forward advancing drive mechanism, the latter can be so controlled in dependence upon the swinging drive, so that during the swiveling motion of the guiding cage downward, i.e., when the lance is directed onto the rear part of the bath, the lance is advanced into the rear of the converter, and during the swiveling of the guiding cage upwards, i.e., when the lance is directed on the front part of the bath nearer the converter opening, the lance is pulled back. The working length of the forward advancing drive mechanism, which is preferably a hydraulic work cylinder, is suitably adjustable, for example telescopically cxtendible. If the working len th of the extendible work cylinder is chosen to be greater than the longest distance by which the oxygen lance penetrates into the converter, then the lance, after the blowing process, can be completely withdrawn out through the blowout opening by further retraction, so that the converter can then be tilted over for discharging.

Further advantages and characteristics of the invention will be apparent from the following description in which the invention is explained in further detail with reference to the accompanying drawings of typical embodiments presented by way of example.

FIG. 1 is a side view of the lance support, guide and driving means according to the invention, with an oxygen lance in position within the blow-out opening of a rotary barrel steel converter, the latter shown in longitudinal section in blowing position;

FIG. 2 is a side view of a swivel drive mechanism for the lance guiding cage:

FIG. 3 is a cross-sectional view taken along line IIIIII of FIG. 2;

FIG. 3a is a view of an alternate type of connecting rod for the swivel drive mechanism;

FIG. 4 is a front view of the swivel drive mechanism according to FIGS. 2 and 3, situated in lower dead center position;

FIG. 5 is an elarged side view of the lance support and guide with a different type of adjustable table for supporting the swivel drive mechanism;

FIG. 6 is a section taken through the guiding cage along the line VI-VI of FIG. 5;

FIG. 7 is a cross section taken on line VIP-VII of FIG. 5; and

FIG. 8 is a schematic layout of the control valve for the reciprocating drive and its connection to operate in dependence on the swivel drive mechanism.

FIG. 1 illustrates a converter vessel 1 in blowing position, with an inserted bottom or floor 2, a refractory lining 3 and containing a molten steel bath 4. The converter vessel 1 is frusto-conically shaped in its front and rear ends, and its intermediate central portion is cylindrical. The inclination of the wall in the conical rear portion of the vessel is such that when the converter is in the inclined position shown, the depth of the bath in the rear portion is approximately constant. In front of the blow-out opening 5 of the vessel 1 there is located a double-Walled water-cooled exhaust-gas hood 6 which is firmly fixed on a base structure 7. The waste-gas hood 6 as well as the base structure '7 may be mounted on a moveable carriage 7a which can move in the direction toward and away from the converter.

Attached to and forming part of the exhaust hood 6 is a conical connection 8 which is likewise cooled by water in its outer shell. An oxygen lance 9, which is provided at its head It) with an oxygen feeding pipe 11 and with cold-water connections and tubes 12, is inserted through the connection 8, across the hood 6, through the blow-out opening 5 into the converter 1. The lance 9 is guided by means of rollers 14 mounted in a guiding cage 13 which is pivotable in a vertical plane about a horizontal axis 46. The guiding cage 13 is provided on its upper end with a short extension arm 15 which is linked to the drive mechanism 19 for swiveling the lance and its support. On the lower end of cage 13 there is porvided a longer arm 16 on which is supported a forward acting pneumatic or hydraulic drive cylinder 17. This cylinder 17 cooperates in synchronization with the swiveling movement of the guiding cage 13 and of the lance 9 and can thus move the lance 9 axially forward and backward, even during its swiveling movement.

The swiveling movement is imparted to the guiding cage 13 and to the lance 9 through a linking member or con necting rod 18 by a crank disc or cam 19. FIG. 2 shows, as an example, one embodiment of these drive members on an enlarged scale. The crank disc 19 is provided with a T-groove 20 in which a pin l9a attached to the end of connecting rod 18 is slidable. The groove 20 permits a change of radius or length of stroke, and thus a change in the swiveling angle at through which the lance 9 will oscillate. The crank disc 19 can be rotated about its central axis by an electric motor 21 provided with a reduction gear drive, by a hydraulic oil motor or by other such drive means. The rational speed of disc 19 may be relatively low, for example 12 to 16 revolutions per minute. In FIGS. 1 and 2 the crank disc 19 is shown directly keyed to the driving shaft Ella of a drive motor 21.

Instead of providing the crank disc 19 with a T-groove as in FIGS. 2 and 3, there can also be used a crank arm for stroke adjustment wherein the arm itself can be adjusted in its length. This embodiment is illustrated in FIG. 3a, wherein the arm 18 is formed in two portions connected by means of a slot and bolts.

Adjustment of the stroke by locating pin 1% at a desired point in the T-groove 24 on the crank disc 19 (FIGS. 2, 3) brings about a change in the amount of swiveling thrust or swing angle 0L of the lance, but not a change in the central swivel position, around which the lance oscillates. A change in location of this central swivel position may become necessary, for example, when one desires to change upwards or downwards by several angle degrees the inclination position (angle (3) of the rotating axis of vessel 1. For this purpose, i.e., to change this central swivel position, the entire drive system can be raised or lowered. In the embodiment according to FIG. 1, the propulsion parts 18, 19 and 21 are arranged on a table 22 supported from the leg 7 of the waste-gas hood 6. The inclination of table 22 can be changed upwardly or down Wardly by means of a spindle 23 provided with a hand wheel 24 mounted in the center thereof. By rotation of the hand wheel 24 it is thus possible to adjust the desired middle swiveling position as well as the position of the reversal points of the axial lance movement.

Instead of the hand wheel and spindle adjustment 23 and 24, mechanical means, such as a hydraulic pressure cylinder (not shown) may also be employed for adjustment of the table 22 For connection to the swiveling drive, a relatively short coupling member 18 is used. If, in crank drives, the length l of coupling members is made rather large in proportion to the crank radius r, then a uniform sinusoidal acceleration rate is attained. It is customary, therefore, for crank drives in general, to select a proportion l/r 4/ l. In'the case under examination, however, the proportion l/ r is preferably about 1.5/1. This produces an uneven rate of acceleration and velocity over the cycle of the stroke, otherwise regarded as a disadvantage; but it is here considered advantageous for the movement of the lance in the converter for reasons explained presently. In the case of a very short coupling member 13 there results at the upper dead center position (see FIG. 2) a relatively high acceleration rate for the upper coupling point 18a, and thus also for the arm 15 and the guiding cage 13. A typical are which point 18a describes during its oscillating motion about point 46 is shown by a dashdot line 18b in FIG. 2.

Correspondingly, for the lower dead center position (see FIG. 4) there results a relatively small acceleration. Starting with upper dead center position, the upper coupling point 18a is brought quickly to its maximum velocity, and this is attained when the coupling member 18 extends tangentially to the crank circle 1%. From this tangent point on, the velocity decreases at a growing rate until member 18 reaches the lower dead center position. In FIG. 2 the crank circle 1% is indicated by a dot-anddash line. The lower coupling point through pin 19a moves along the crank circle 1% with constant velocity.

The velocity change curve of the upper coupling point 13a is indicated as a dotted line 19c around the crank circle 1%.

The upper coupling dead center position corresponds to the reversal point of the moving oxygen jet in the front part of the molten bath 4, i.e., relative to opening 5. In the above-described manner, with the apparatus according to the invention, there is attained a relatively short period of stay of the jet on the surface of the bath in the range of the front reversal point of the oxygen jet, and in the range of the rear reversal point a correspondingly longer period of stay is attained.

As shown in 1 16.3, the coupling member 18 is connected one-sidedly both at the crank disc 19 and also at the cage arm 15, that is flyingly, and the crank disc 19 and the arm 15 are arranged at the respectively opposite sides of the coupling member 18. The coupling member lit can be even a little shorter than the proportions given in the illustrated embodiment. However, a lower limit of length is practically set by the fact that as the coupling member 18 becomes shorter, the lateral force components utlimately become too great due to the increasingly inclined position of the coupling member.

Since the coupling member. 18 is a very simple structural unit and can be easily exchanged for shorter or longer coupling members, its installation according to the present invention can be adjusted to suit the requirements of various forms of the converter vessel, Without the need for making substantial changes.

FIG. 5 illustrates a modified embodiment of the lance support and guide according to the invention, shown with the lance located in the upper position and advanced completely forward. The movement mechanism for the lance in this embodiment is mounted on arigid service platform 25 which extends transversely and which can be equipped with a handrail, an access ladder, and the like (not illustrated).

Adjustment of the middle swiveling position of the lance is accomplished by means of a table 27 pivotable around a shaft 26 supported from journals fixed to platform 25. This table 27 can be adjusted in its inclination by means of a compression-screw spindle, which is supported by the platform 25. In order to permit the spindle 28 during its adjustment to follow without binding the circulararc traversed by the end of the table 27 during pivotal adjustment of the latter around its shaft 26, the spindle nut 29 is positioned rotatably in the platform 25; and the spindle disc Bil, which supports the free end of the table 27, is given a concave spherical shape, while the lower side of the hand wheel 31 is given a .mating convex spherical shape. The piston rod 32 of the cylinder 17 is fastened to an entraining member 33 which is formed as a hinged clamp and surrounds a projection extending from the head 1% of the lance. After release of the wing nut 3 and displacement of the eye screw 35, the lower part 36 of the clamp can be swung down and thus the entraining member 33 can be separated from the lance. To be exchanged, the lance can readily be removed by pulling it out longitudinally from the cage 13.

.Welded directly onto the lance 9 are guide rails 40, having, for example, a rectangular profile.

FIG. 6 shows in cross section the arrangement and positioning of lance guiding rollers 41 and 42 along which the rails 4t! ride. The rollers 41. and 42- and the guide rails 44 are so arranged that the shafts of the rollers 41 and 42 as well as all surfaces of the rails 4! always occupy an angle of 45 degrees in relation to the horizontal level. This offers the advantage that no dust can settle down on the surfaces of the rail head. No dust can accumulate on the inclined rail surfaces, due to the considerable currents of gas in the waste-gas hood, and due also to the oscillating movement of the lance. A similarly advantageous position of the bearing surfaces of the rails results with a symmetrical arrangement of three guide rails on the periphery of the lance, if one of the three rails is mounted on the lower side of the lance, that is on the lowest generatrix line of the cylindrical lance pipe.

However, some dust could be deposited on the upper lateral surfaces of the two upper guiding rails dd. For this reason, the two upper guiding rollers 42; are formed without wheel flanges on their upper sides. The guide cage 13 has openings through which the inside can be serviced and, if necessary, can be blown out with com pressed air. Furthermore, it is possible to fixedly install at the entrance to the cage a ring-shaped pipe with blowing openings directedonto the rails or with single orifices directed on rails as a compressed air rail cleaner. At the entrance to the guide cage it is also possible to provide mechanically-operated rail cleaners, for example, wire brushes or the like.

As can be seen from FIG. 6, the rollers 41 and 42 are positioned on eccentric shafts or bolts 43. After the nuts 44 thereon are loosened, the eccentric shafts 43 can be 6 turned by means of a square head 45, so that the play of the rollers can be positioned and adjusted exactly, and when the guiding rails it) are worn down, the play can be similarly taken up.

The guiding cage 13 according to FIGS. and 6 comprises two parts screwed together at their flanges. This manner of construction allows an advantageous mounting, especially of the guiding rollers 41 and 42. The guiding cage can, however, be made in one piece, for example as a casting construction. For a separate-part construction of the guiding cage the arrangement of four running rails on the lance is expedient, because in this manner the two parts of the cage to be screwed together can be identical. For a one-piece cast cage it is preferable, however, to have one in coordination with a lance equipped with three running rails, because in this manner fewer running rollers are required to maintain reliable axial guidance of the lance.

On the lower end of the guiding cage 13 are fastened pins 46 which are journaled in bearings 47 to define the pivot axis 46 about which the lance swings. The bearings 47 are fastened on a rectangular end-supporting cover plate 48. The pins 46' are mounted as close as possible to the through-opening of the cover plate For this reason, the openings in part 48 for passing the lance through are relatively small, despite the space needed for the swiveling movement of the lance, indicated in PEG. 7 by dotand-dash lines.

PEG. 7 illustrates the fact that the water-cooled endconnection 8 consists of an outer sheet metal covering wall 49 and an inner sheet metal covering wall Sh. Both sheet metal covering walls are made up of two half-cups welded together, and placed so as to curve around the swiveling space of the lance.

FIG. 8 illustrates schematically a rotary valve V for controlling the reciprocating hydraulic cylinder 17. The valve V is driven through a reduction gear from the same motor 21 which drives the oscillation coupling member 18. In this manner, synchronization is achieved between the reciprocating drive 17 and the oscillating drive 18, 19.

The end-connection 8 (FIG. 1) is shaped as a frustoconical body and thus has a high degree of rigidity of form. Besides, since it is also supported by the base frame structure 7, all forces caused by the movement of the lance can be reliably restrained, even when the endconnection 8 is made from thin sheet metal for better heat conduction.

At the highest point of the end-connection 8 there is installed a fitting 51 for the cooling-water outlet, positioned in such manner that it will not interfere with the arm 16 during the swiveling movements of the latter.

Due to the usually yielding covering wall structural form of the waste-gas hood, the above-described construction of the means for insertion of the lance entails no danget of rupture nor cause for any other operating dis- 1 turbances.

Through the arrangement of, for example, a telecsopically extending cylinder 17 with a longer stroke path, the lance 9 may be withdrawn completely thereby out through the converter opening 5, so that the converter 1 can then be immediately tilted over for discharge without further ado.

The lance support and conducting means according to the present invention can be subject to some modifications. For example, in special cases it may be expedient, by omitting the guiding member or the guiding cage, to mount the lance swivelingly in a pivoted support directly on the waste-gas hood or on the oxygen feeding connection 11. Likewise, according'to the invention, the arrangement for axial displacement of the lance can be made suitably independent from the new swiveling apparatus. It is also possible to position the horizontal pivoting axis 46 of the guiding member not at the height of the central longitudinal plane of the lance, but at a distance above or below it, so that not only a purely swinging movement is impartedto the lance by the swivel drive; but a sort of forward and backward motion as well. In this case, the opening in the exhaust hood for introduction of the lance must be elongated or slot-shaped to a greater extent or be slidably adjustable. This latter type lance support and conducting means can also be advantageously used for additional lances.

It will be obvious to those skilled in the art, upon studying this disclosure, that devices according to the present invention can be modified in various respects and hence may be embodied in apparatus other than particularly illustrated and described herein, without departing from the essential features of the present invention and within the scope of the claims annexed hereto.

What is claimed is:

1. Apparatus for supporting and driving a moving oxygen lance in the rotary barrel converter process of steel production, said apparatus comprising a lance supporting member for receiving an oxygen lance and adapted to direct same through the converter outlet opening onto the surface of a bath of steel during converter operation, said supporting member being mounted for pivotal movement about a predetermined substantially horizontal axis to direct said lance sequentially toward rearward and forward portions of said bath surface relative to said converter opening, a drive mechanism for imparting cyclical oscillating motion about said axis to said supporting member and thus to said lance, and linking means connecting said drive mechanism with said supporting member so thatsaid supporting member travels at a greater angular velocity for the cycle period portion corresponding to the time when the lance is moving over'said forward portion of the bath surface, as compared to the other portion of the cycle of said oscillating motion, said forward portion comprising the portion of the bath over which the lance is directed between its pivotal position when directed closest to said converter opening and approximately the middle pivotal position of its swing.

2. Apparatus for supporting and driving a moving oxygen lance in the rotary barrel converter process of steel production wherein an exhaust hood is positioned in front of the converter outlet opening for receiving waste gas during the converter operation, said apparatus comprising a lance guide member for receiving an oxygen lance and adapted to direct same through said converter opening onto the surface of a bath of steel therein during said operation, said guide member being mounted on said hood for pivotal movement about a substantially horizontal axis to direct said lance sequentially and cyclically onto rearward and forward portions of said bath surface relative to said converter opening, and a drive mechanism for imparting cyclical oscillation motion about said axis to said guide member and to said lance, said drive mechanism comprising rotary crank means and a coupling member connecting said crank means with said guide member, the ratio of the length of said coupling member to the radius of said crank means being approximately 1.5 so that said guide member travels at a greater angular velocity about said axis for the cycle period portion corresponding to the time when the lance is moving over said forward portion of the bath surface, as compared to the other portion of the cycle of said oscillating motion.

3. Apparatus according to claim 2, said crank means including means for adjusting said radius thereof.

4. Apparatus according to claim 2, including table means for supporting said drive mechanism, and means for adjusting the height of said table means relative to said axis of said guide member.

5. Apparatus according to claim 4, said table means being pivotally mounted on a portion of said hood and rotatably adjustable about a substantially horizontal axis, and spindle means disposed between said table means and the lower portion of said hood for adjusting the height and inclination of said table.

6. Apparatus for supporting and driving a moving oxygen lance in the rotary barrel converter process of steel production wherein an exhaust hood is positioned in front of the converter outlet opening for receiving Waste gas during the converter operation, saidapparatus comprising a lance guide member for receiving an oxygen lance and adapted to direct same through said converter opening onto the surface of a bath of steel therein during said operation, said guide member being mounted on said hood for pivotal movement about a substantially horizontal axis to direct said lance sequentially and cyclically toward rearward and forward portions of said bath surface relative to said converter opening, said guide member being provided with a connection plate having journal means fixedly attached thereto defining said pivotal axis, a frusto-conical tubular connection piece forming part of said Waste-gas hood for fixedly supporting said connection plate, and a drive mechanism having cam means for imparting cyclical oscillation motion about said axis to said guide member and to said lance so that said guide member travels at a greater angular velocity about said axis for the cycle period portion corresponding to the time when the lance is moving over said forward portion of the bath surface, as compared to the other portion of the cycle of said oscillating motion, said forward portion comprising the portion of the bath over which the lance is directed between its pivotal position when directed closest to said converter opening and approximately the middle pivotal position of its swing.

'7. Apparatus according to claim 6, said tubular connection piece being double-walled and defining an interspace for the circulation of cooling water therethrough, bracing means joining the lower portion of said wastegas hood with said tubular connection for supporting the latter on said hood, and driving means for changing the longitudinal position of the lance in the converter simultaneously with said oscillating motion of the lance.

8. Apparatus according to claim 2, including an access platform fixedly mounted onto a portion of said hood, table means for supporting said drive mechanism movably attached to said platform, means for adjusting the height of said table means, and driving means for changing the longitudinal position of the lance in the converter simultaneously with said oscillating motion of the lance.

9. Apparatus for supporting, driving and guiding a moving oxygen lance in the rotary barrel converter process of steel production wherein an oxygen lance in the form of a pipe is provided with longitudinal running rails spaced about its periphery, a lance guide member for receiving and axially guiding said lance therethrough and adapted to direct same through the opening of said converter onto the surface of a bath of steel therein during operation thereof, said guide member comprising a pinrality of guide rollers disposed around said lance and having peripheral rolling surfaces engageable with the respective running rails of said lance, a reciprocating drive attachable to said lance for moving the latter axially back and forth through said rollers to direct the terminal end i of said lance across said bath surface, and an oscillating drive mechanism attached to said guide member for swinging the latter about a substantially horizontal axis during said back and forth movement therethrough of the lance.

ill. Apparatus according to claim 9, said lance being provided with four of said running rails equi-distantly spaced about the lance periphery, and said guide rollers being rotatably positioned in said cage so that said peripheral guide surfaces thereof as well as the lance running rail surfaces engaged thereby all occupy an angle of approximately 45 relative to a vertical central longitudinal plane passing through the lance.

ill. Apparatus according to claim 9, said lance being provided with three of said running rails symmetrically spaced about the lance periphery, one of said running lb rails being installed along the lowermost longitudinal edge of said lance.

12. Apparatus according to claim 9, including control means interconnecting said reciprocating drive with said oscillating drive for synchronizing the two drives in such manner that during swiveling of the lance from a position over the front area of the bath surface to over its rear area the lance is propelled into the converter, and during the opposite swiveling movement the lance is retracted.

13. Apparatus according to claim 9, said. reciprocating drive having means for adjusting the length of the working stroke thereof.

14. Apparatus according to claim 13, the length of said working stroke of said reciprocating drive being adjustable to a stroke longer than the longest distance which the terminal end of said lance penetrates into the converter.

15. Apparatus according to claim 9, said reciprocating drive comprising a hydraulic cylinder, said guide member being provided at one end thereof with an end member for pivotally journalling said guide member and having an opening for passing the lance therethrough, an entraining member for gripping the lance near the opposite end of said guide member, and said hydraulic cylinder being mounted above said guide member and connected between said end member and said entraining member.

16. Apparatus according to claim to, said entraining member comprising a hinged clamp having means for ready detachment thereof from said lance, the head portion of said lance being provided with an annular groove for attaching said clamp.

17. Apparatus according to claim 9, said guide rollers having axle shafts on which the guide rollers are rotatably mounted, said shafts having eccentric portions for radial adjustment of said rollers toward and away from the longitudinal axis of said lance.

18. Apparatus according to claim 9, aid guide member being provided at the lower portion thereof with cleaning means for removing dust from said running rails.

19. Apparatus for supporting and driving a moving oxygen lance in the rotary barrel converter process of steel production, said apparatus comprising a lance supporting member for receiving an oxygen lance and adapted to direct same through the converter outlet opening onto the surface of a bath of steel during converter operation, said supporting member being mounted for pivotal movement about a predetermined substantially horizontal axis to direct said lance sequentially toward rearward and forward portions of said bath surface relative to said converter opening, a drive mechanism for imparting cyclical oscillating motion about said axis to said supporting memher and thus to said lance, and linking means connecting said drive mechanism with said supporting member so that said supporting member travels at a greater angular velocity for the cycle period portion corresponding to the time when the lance is moving over said forward portion of the bath surface, as compared to the other portion of the cycle of said oscillating motion, and driving means for changing the longitudinal position of the lance in the converter simultaneously with said oscillating motion of the lance.

20. Apparatus according to claim i, said drive mechanism including a crank disc and means for continuously rotating same, said linking means including a connecting rod pivoted at one end thereof to said disc and at the other end thereof to said supporting member.

21. Apparatus according to claim ll, said drive mechanism including a crank disc having a T-groove therein and means for continuously rotating said disc, said linking means including a connecting rod pivoted at one end thereof to said disc at said T-groove for radial adjustment of said one end relative to the center of said disc, said connecting rod being pivoted at the other end thereof to said supporting member.

22. Apparatus according to claim 1, said drive mechanism including cam means and means for continuously References flier! by the Examiner rotating said cam means at a constant rotational speed, UNITED STATES PATENTS said linking means including cam follower means con- 1 v i V a necting said cam means with saio supporting means for 6 10/62 V Ohlnhrt et 266 36 transforming the constant rotational speed of said earn 5 FOREIGN PATENTS means into angular motion of continuously variable cycli- 1 19 391 11 59 France cal motion so as to cause greater angular velocity over 7 said first named cycle period portion as compared to said MORRIS W Examine"- other cycle period portion. RAY K. WINDHAM, Examiner. 

1. APPARATUS FOR SUPPORTING AND DRIVING A MOVING OXYGEN LANCE IN THE ROTARY BARREL CONVERTER PROCESS OF STEEL PRODUCTION, SAID APPARATUS COMPRISING A LANCE SUPPORTING MEMBER FOR RECEIVING AN OXYGEN LANCE AND ADAPTED TO DIRECT SAME THROUGH THE CONVERFTER OUTLET OPENING ONTO THE SURFACE OF A BATH OF STEEL DURING CONVERTER OPERATION, SAID SUPPORTING MEMBER BEING MOUNTED FOR PIVOTAL MOVEMENT ABOUT A PREDETERMINED SUBSTANTIALLY HORIZONTAL AXIS TO DIRECT SAID LANCE SEQUENTIALLY TOWARD REARWARD AND FORWARD PORTIONS OF SAID BATH SURFACE RELATIVE TO SAID CONVERTER OPENING, A DRIVE MECHANISM FOR IMPARTING CYCLICAL OSCILLATING MOTION ABOUT SAID AXIS TO SAID SUPPORTING MEMBER AND THUS TO SAID LANCE, AND LINKING MEANS CONNNECTING SAID DRIVE MECHANISM WITH SAID SUPPORTING MEMBER SO THAT SAID SUPPORTING MEMBER TRAVELS AT A GREATER ANGULAR VELOCITY FOR THE CYCLE PERIOD PORTION CORRESPONDING TO THE TIME WHEN THE LANCE IS MOVING OVER SAID FORWARD PORTION OF THE BATH SURFACE, AS COMPARED TO THE OTHER PORTION OF THE CYCLE OF SAID OSCILLATING MOTION, SAID FORWARD PORTION COMPRISING THE PORTION OF THE BATH OVER WHICH THE LANCE IS DIRECTED BETWEEN ITS PIVOTAL POSITION WHEN DIRECTED CLOSEST TO SAID CONVERTER OPENING AND APPROXIMATELY THE MIDDLE PIVOTAL POSITION OF ITS SWING. 